**3.
Do most of the points seem to come close to falling on a line? One way to tell is to draw
a small circle around the point. The smaller the circle, the closer the points are to
lining up. The larger the circle the less they fall in a straight line.**

**4. Draw a line through the middle of your scatter
plot. The line should also run through the center of your circle.**

**5. Your line is a geometric model for the
relationship between height and shoe size.**

**You can use your model to estimate your shoe size. Find your height on the
horizontal scale and move upward until you come to the line. Then move to the left until
you come to the vertical scale. Read your predicted shoe size.**

**What shoe size was predicted?____________**

**How does the predicted shoe size compare with your actual shoe
size?_______________________**

**6. Choose two points on your line whose
coordinates are integers. They do not have to be points of your original data but should
be fairly far apart. Record the coordinates of the points below:**

**_____________ ____________**

**7. Use the two points to find the slope of the
line. ___________________**

**8. Use the slope and one of your two points to
find the y-intercept (0, b) of the line. Write the y-intercept and the equation of the
line below:**

**y-intercept: ___________________**

**equation: ____________________**

**9. Your equation is an algebraic model for the
relationship between height and shoe size.**

**Use this model to calculate your predicted shoe size. Do this by substituting
your height for x in the equation and rounding the shoe size to the nearest 0.5.**

**What shoe size was predicted? _____________**

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**11.**Compare you misses with those of another student.
Whose line did the best job of predicting shoe sizes for members of your class? Why?

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****12. **a. According to the *Guinness Book of World
Records*, the tallest person who ever lived was Robert Wadlow, who was 8 ft, 11 inches
tall.

What shoe size would you predict for him?__________

b. The tallest living women is Sandy Allen at 7 feet, 7 inches.

What shoe size does your equation predict for her?___________

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****13. **What shoe size does your equation predict for a
person who is 50 inches tall?_____________

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